Portable internal combustion engines are used in a wide variety of applications, such as lawn mowers, snow blowers, chain saws, electrical generators, pressure or power-washers, etc. It is appreciated that such devices can commonly be provided a manual start configuration and/or an electric start configuration. Those skilled in the art will appreciate that manual start engines often include a recoil assembly and that power or electric starting systems commonly include an electric starter, the respective operation of which generates the initial compression cycle associated with self-sustainable operation of the underlying engine. Some engine powered devices are provided with both manual and electric starting systems to improve the redundancy with which the user is able to start the underlying engine.
As those skilled in the art can attest, starting and maintaining operation of the internal combustion engine of many portable engine driven devices commonly requires user interaction with various discrete controls associated with starting and operating the internal combustion engine during different conditions. Many portable engine powered devices, whether equipped in a manual or electronic starting configuration, require sequential user interaction with various controls to effectuate starting and maintaining operation of the engine. The sequence and relative degree of operation of these various controls also frequently varies as a function of ambient and contemporaneous conditions associated with operation of the internal combustion engine as explained further below.
Manually started engines commonly include an ON/OFF switch or key switch associated with communicating an electrical signal to a spark plug during operation of the recoil as well as operation of the engine after the engine has started. Such engine ignition systems commonly provide a shunt, fault, or ground connection associated with turning the engine OFF as the fault suspends generation of the spark signal. The internal combustion engine cannot be started during operation of a recoil or a starter when the fault condition exists. Accordingly, one aspect of starting any engine is to attend to the electrical ignition system of the engine to ensure a spark signal will be generated during operation of the recoil or starter.
Another consideration to ensure efficient or expeditious starting of the engine is the communication of a desired charge of a combustion charge to the combustion chamber. Many portable engine powered devices include a manually operable fuel valve and one or more of a choke or choke control, a primer or primer control, and/or an engine throttle control that can each contribute to manipulation of the respective ratio of fuel to air associated with the combustion charge. That is, manipulation of a fuel valve and any of the fuel or combustion charge flow controls alters the amount of fuel and/or air provided to the combustion chamber and/or the throttle assembly and affects starting and/or subsequent self-sustained operation of the underlying engine. Failure to properly attend to the fuel valve, choke, throttle, and/or primer controls can prolong the efforts associated with starting the engine.
Commonly, the controls associated with user interaction with the ignition system, choke, throttle, primer, and/or fuel valve systems are disposed in various discrete positions about the underlying device. For instance, many such devices include a fuel valve disposed near the outlet of the fuel reservoir or tank, an ignition system control—frequently simply one or more ON/OFF keys or switches, are commonly disposed on a dashboard or side surfaces of the device, and choke controls that are commonly disposed proximate a dashboard or the throttle assembly associated with operation of the underlying engine. Devices equipped with power starting systems can also occasionally include respective first and second switches that are associated with completing the ignition signal circuit and selective activation of the electric starter. Efficient starting of the engine associated with such devices includes a requisite degree of familiarity with the desired sequence and direction of operation of each of the controls as well as the location of the discrete controls relative to the underlying device.
Further complicating engine starting performance, the user must also consider the current or recent engine operating conditions in addition to the location and manipulation of the ignition and fuel controls discussed above. For instance, when attempting to start a “cold” engine or engine that has not be operated for some duration, it is commonly necessary to choke the throttle and/or prime the engine. Once the engine turns over under its own power, the user must commonly manipulate one or more of the choke, the throttle, and/or a primer to maintain self-sustained operation of the engine. Failure to properly attend to one or more of the choke, throttle, and/or primer controls in a manner and/or sequence specific to the operating characteristics associated with the engine can result in “flooding” of the engine or a condition wherein too much fuel or too rich of a combustion charge is present in the combustion chamber to effectuate starting and sustained operation of the engine. Although a flooded engine can commonly be started with subsequent starting efforts—such as manipulation of the fuel and throttle controls and pulling of the recoil or activation of the starter, recovering from a flooded engine condition only frustrates a user's ability to expeditiously start the affected engine.
For those conditions where an engine has been operated for a sufficient duration so as to “warm-up” or even reach a normal operating temperature, subsequent starting sequences are not commonly the same as the cold engine starting sequence. That is, a warm engine will commonly start with no or only minimal manipulation of any of the choke and/or throttle systems from a normal operating orientation. The various nuances associated with engine starting sequences, the various locations associated with generation of the spark electronic signal, priming, choke, and/or throttle controls, and the desired sequencing associated with the manipulation of such controls can frustrate the ability of even experienced user's to efficiently start an engine associated with many portable engine powered devices.
Suitable user interaction with the various controls, particularly novice or first time users or even users who have not started or operated the respective devices for an extended period, commonly requires user inspection of the entirety of the device to gain or regain understanding of the location, direction of operation, sequence of operation, and/or the range of motion associated with each of the respective controls. Failure to adequately understand the respective orientation and sequencing of the various engine operating controls can result in the undesirable flooding of the engine and/or self-sustained but less than efficient operation of the underlying engine.
Therefore, there is a need for a control assembly for portable engine powered devices that is convenient and easy to understand and which manipulates more than one of the ignition and fuel system controls to simplify starting, stopping, and self-sustained operation of the internal combustion engine.